Centrifugal spiral band locking device,especially for self-destroying fuzes



June 23, 1970 WEBER ET AL 3,516,359

CENTRIFUGAL SPIRAL BAND LOCKING DEVICE, ESPECIALLY FOR SELF-DESTROYING FUZES Filed Jan. 25, 1968 4 Sheets-Sheet 1 Fig I uvmvrom R- We 56 r- BY WinCGrkzZZef- June 23, 1970 WEBER ET AL 3,516,359

CENTRIFUGAL SPIRAL BAND LOCKING DEVICE, ESPECIALLY FOR SELF-DESTROYING FUZES Filed Jan. 25, 1968 4 Sheets-Sheet 2 INVENTOR) 6 l- R. WEBER ET AL 3,516,359 RAL BAND LOCKING DEVICE, ESPECIALLY FOR SELF-DESTROYING FUZEQ June 23, 1970 CENTRIFUGAL SP1 4 Sheets-Sheet 3 Filed Jan. 25, 1968 Fig. 4

INVENTORS RvuL f Wezael' WaZZ eI- BY WL nZ erLzZ tel- June 23, 1970 R. WEBER ET AL 3,516,359

CENTRIFUGAL SPIRAL BAND LOCKING DEVICE, ESPECIALLY FOR SELF-DESTROYING FUZES Filed Jan. 25, 1968 4 Sheets-Sheet 4 Fig.6 5

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Fig. 8

INVENTORS R. Weber W Win Zei-ka Zlez- United States Patent 3,516,359 CENTRIFUGAL SPIRAL BAND LOCKING DEVICE, ESPECIALLY FOR SELF-DESTROYING FUZES Rudolf Weber, Schramberg, and Walter Winterhalter, Lautherhach, Wurttemberg, Germany, assignors to Gebruder Junghans G.m.b.H., Schramberg, Wurttemberg, Germany Continuation-impart of application Ser. No. 418,216, Oct. 14, 1964. This application Jan. 25, 1968, Ser. No. 700,472

Int. Cl. F42c 15/22, 15/04, 15/20 US. Cl. 102-79 2 Claims ABSTRACT OF THE DISCLOSURE A fuze for rotating projectile with direct impact ignition and a self-destroying device, in which a fuze body has a firing pin and various elements including a locking device with a core sleeve of a plurality of connected elements within a centrifugal spiral member.

This application is a continuation-in-part of the copending application Ser. No. 418,216 filed Oct. 14, 1964, now abandoned.

It is known in connection with rotating projectile fuzes to lock the axial firing pin bolt by a centrifugal spiral element located behind a collar on the pin bolt. The centrifugal spiral element is wound around a core sleeve in which a centrifugal segment is mounted which engages behind the firing pin bolt flange. Its flying out and consequently the release of the pin bolt are retarded by the centrifugal spiral element.

Such a core sleeve is generally produced by turning and milling; a machining operation which is expensive.

The object of the invention is to simplify and reduce the cost of this locking device. It saves the centrifugal segment mounted in the core sleeve and can be produced by a cheap stamping or embossing process.

These advantages are attained in that, according to the invention, the core sleeve consists of a thick profiled band the inner side of which has transverse notches of triangular cross-section which are so deep that coherent band elements of quadrangular cross-section are formed, the number of notches and their angle of slope being so chosen that, when the band is bent to form the sleeve, its outer surface forms a polygon. It may also be advantageous to provide an outer flange on the upper and lower edges of the profiled band.

Two embodiments of the invention are illustrated by way of example in the accompanying drawings, in which;

FIG. 1 is a longitudinal section taken on line II of FIG. 2, which shows a self-destroying fuze with the new locking device;

FIG. 2 a cross-section taken on line II-II of FIG. 1 showing the fuze in locked condition;

FIG. 3 is a similar view to FIG. 2 showing the fuze in released condition;

FIG. 4 is a part longitudinal section of the fuze taken on line IV1V of FIG. 5;

FIG. 5 is a cross-section taken on line VV of FIG. 4, showing the fuze in locked condition;

FIG. 6 is a diametric view of the inner side of the profiled band;

FIG. 7 is a diametric view of the profiled band bent to form the winding core;

FIG. 8 is a diametric view of a modified form of construction of the profiled band, viewed from the inner side thereof, and;

Patented June 23, 1970 ice FIG. 9 is a diametric view showing the band according to FIG. 8 bent into the form of a winding core.

In FIG. 1 only the parts of the fuze are shown which are of importance for the invention. Element 10 is the firing pin bolt in the space and on to which the flange 11 is lipped from the rear. Behind this, in position of rest, is a core sleeve 14, around which a centrifugal band spiral 12 is wound which is held in wound state by a blade spring 13 bent in the form of a ring.

The band spiral 12 preferably consists of a soft material such as Cu or Al, whereas the ring-shap d blade spring 13 holding it together is of hard spring steel.

The core sleeve 14 is made from a thick section band which is shown in stretched state in FIG. 6. It has on its inner side a number of notches 15 of triangular crosssection. They are of such a depth that the band is divided in to coherent elements. The number of these elements corresponds to the intended shape of the core sleeve, which is to be polygonal. The angle of slope of the sides of the triangular cross-sections must correspond to the angle between the radii of the polygon.

The profiled band shown in FIG. 6 has six band elements the outer surfaces of which form a hexagon. The thickness of the profiled band should only be so great that the firing pin bolt can still pass through the centre of the sleeve.

As can be seen from FIG. 1, the hexagonal sleeve is directly behind the firing pin bolt 11. The centrifugal band spiral 12 is wound around the outer side of the sleeve 14 and in turn is held together in position of rest by the centrifugal band spring 13, shown in FIG. 2. Through the rotation of the fuze, the leaf spring 13 bends open and bears against the inner wall of the fuze bore. Then the centrifugal band spiral 12 unwinds and bears against the inner side of the bent blade Spring 13. Finally, the centrifugal force also causes the winding sleeve 14 to expand and bear against the inner side of the centrifugal band spiral wound on it. As a result, the pin bolt 10 is relieved of its support and released, as shown in FIG. 3.

Making the core sleeve by merely bending a stamped or embossed profiled band enables the fuze to be easily assembled, the assembly being further facilitated by the fact that the centrifugal band spiral can be wrapped around the polygonal wall of the core sleeve without it being necessary to hold or fix the spiral band.

Owing to the omission of the centrifugal segment hitherto located in the core sleeve, the sleeve can be smaller so that more space is available for the centrifugal spiral which then results in a longer safety period in front of the barrel.

Another advantageous construction of the new core sleeve is shown in FIGS. 4, 5, 8 and 9.

Here the sleeve is again composed of a coherent profiled band bent in the form of a polygon. In this case the profiled band has on its upper and lower edges an external flange 16 so that a recess 17 is formed between the two flanges.

In this form of construction the centrifugal spiral 12 is wound in the recess and consists of a multilayer wire coil which is held by the centrifugal band spring 13'.

This locking device operates in the same manner as that already described.

It is further pointed out that the core sleeve 14 is directly mounted around the thin shaft of the firing pin 10 and therefore for this reason the outer circumference of the sleeve is small and further for this reason a comparatively larger space is created for a long centrifugal safety band 12. The space 15 has provided therein a spring 16' and a hammer sleeve 17' to cooperate with the pin 10. Between the fuze head and the pin 10 there is provided a space 15' and adjacent the hamm r sleeve 17' there is provided a centrifugal decomposing device having an end member to lock the hammer sleeve 17 in position which may be set free so that then the spring 16' will force the hammer sleeve 17' on the flange 11 and the firing pin can pierce a detonator.

We claim:

1. A core element for use in a fuze of a projectile to surround a firing pin comprising a plurality of interconnected members forming a sleeve around the pin with each member having a plurality of plane figure surfaces each in the configuration of a polygon.

2. A core element according to claim 1, in which each end of the sleeve is provided with a circumferential flange.

References Cited UNITED STATES PATENTS 3,076,410 5/1963 Guerne. 1,216,802 2/1917 Hawkins 10279 FOREIGN PATENTS 280,859 1/1928 Great Britain.

10 BENJAMIN A. BORCHELT, Primary Examiner T. H. WEBB, Assistant Examiner US. Cl. X.R. 

